[PATCH] D48374: [mips] Sign extend i32 return values on MIPS64

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: include/llvm/CodeGen/TargetLowering.h:2140
+  /// combined in certain conditions.
+  virtual bool keepSextInRegNode(EVT VT) const {
+    return false;
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Is this required for correctness?  If it is, then the MIPS target is lying to DAGCombine somehow, and this fix is just papering over the bug.  Otherwise, I can't see how keeping around a redundant SIGN_EXTEND_INREG would make the generated code more efficient.


https://reviews.llvm.org/D48374